The heart of the Acolyte derailleur is its innovative SpringLock system. By pairing a customized linear rate high tension spring and a dual stage activation mechanism, Microshift developed a system that can provide substantial chain security when you need it and can be turned off when you don’t. To engage the clutch, turn the engagement bolt clockwise until it clicks. There’s no way to overtighten the bolt. To disengage the clutch for wheel removal, flip the switch. It’s that simple. Innovative SpringLock chain retention keeps chain in place over rough terrain. Direct path cable routing for smooth and responsive shifting. Compatible with 12-42T and 12-46T 8-speed cassettes. Compatible with Acolyte shifters only. Max cog: 42-46T. Capacity 41T.